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Hirakawa, M. P.

Publications and source records attributed to Hirakawa, M. P..

3 recordsLinked to original sources

Multi-omic and phenotypic analysis of growth and resilience of open raceway pond production of Monoraphidium minutum 26B-AM

BackgroundGreen microalgae, such as Monoraphidium minutum 26B-AM, have garnered significant commercial interest due to their high biomass production and lipid yield, providing promising candidates for various bioprocessing applications. However, the economic viability of large-scale algal cultivation in open raceway ponds is limited by biocontamination and environmental stressors, necessitating deeper understanding of the molecular mechanisms that underpin resilience and productivity in these systems. We hypothesized that the molecular signature associated with the cellular responses of M. minutum to environmental stressors will reveal critical information for the timely prediction of resilience and productivity in algal cultures within open pond systems. ResultsTo test this hypothesis, we conducted a longitudinal multi-omic study, integrating transcriptomics, proteomics, metabolomics, and phenomics, to monitor the acclimation, growth dynamics, and pathogen responses of algal cultures in two 1000 L raceway ponds, before and after the introduction of a pathogen as a stressor. We identified a number of molecular patterns that correlate with changes in the algal environment, and we can track these changes within the ponds per time. Furthermore, we identify scale-up and infection-specific molecular pathways through integrated multi-omics, showing that most patterns are unique to each studied stressor/transition. ConclusionsUltimately, this study demonstrates the utility of multi-omics observations at scale, revealing unique signatures and laying the groundwork for developing molecular detection techniques and predictive models that can improve the sustainability and efficiency of large-scale algae biomass production.

molecular biology↗

Augmentation of Antibacterial Activity in Mesenchymal Stromal Cells Through Systems-Level Analysis and CRISPR-mediated Activation of CD14

Mesenchymal stromal cells (MSCs) have broad-ranging therapeutic capabilities, however MSC use is confounded by cell-to-cell heterogeneity, and source-to-source phenotypic inconsistencies. We utilized a systems-based approach to compare MSCs which displayed different capacity for antibacterial activity. Although MSCs from both sources satisfied traditional MSC-defining criteria, comparative transcriptomics and quantitative membrane proteomics demonstrated two unique molecular profiles. The antibacterial MSCs respond rapidly to bacterial lipopolysaccharide (LPS) and have elevated levels of the LPS co-receptor CD14. CRISPR-mediated overexpression of endogenous CD14 in non-antibacterial MSCs resulted in faster LPS response and enhanced antimicrobial activity. Single-cell transcriptome profiling of CD14-activated MSCs revealed uniform enhancement of LPS response kinetics, and a shift in the ground state of these MSCs. Our results demonstrate that systems-level analysis can reveal critical molecular targets to optimize desirable properties in MSCs, and that overexpression of CD14 in these cells can shift their state to be more responsive to future bacterial challenge.

molecular biology↗

A Global Analysis of Mutations Accompanying Microevolution in the Heterozygous Diploid Pathogen Candida albicans

Candida albicans is a heterozygous diploid yeast that is a commensal of the human gastrointestinal (GI) tract and a prevalent opportunistic pathogen. Here, whole-genome sequencing was performed on multiple C. albicans isolates passaged in different niches to characterize the complete spectrum of mutations arising during microevolution. We reveal that evolution during short time-scales (<600 generations) is driven by both de novo base substitutions and short-tract loss of heterozygosity (LOH) events. In contrast, large-scale chromosomal changes are relatively rare, although chromosome 7 trisomies repeatedly emerged during passaging in one GI colonization model. Both strain background and chromosomal features affected mutational patterns, with mutation rates being greatly elevated in regions adjacent to emergent LOH tracts. Mutation rates were also elevated during host infection where genomes showed strong evidence of purifying selection. These results establish the genetic events driving C. albicans evolution and that this heterozygous diploid is extensively shaped by purifying selection.

genomics↗